亚精胺对番茄幼苗高温胁迫伤害的缓解作用
时间:2018-07-12 10:41 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：本实验以番茄品种‘浦红968’为试材，采用基质栽培的方式，设置了常温叶施（叶面喷施）蒸馏水、常温叶施亚精胺（Spd）、高温叶施蒸馏水、高温叶施Spd四个处理，研究叶施外源Spd对番茄幼苗在高温胁迫条件下生长发育的作用。结果表明试材地上部及地下部干重在高温胁迫条件下显著降低，胁迫条件下施用Spd处理后，番茄叶片的地下部干重有显著性的提高，增加了5.79%，但仍然与对照组有显著性差异，地上部干重同样上升并且恢复至正常水平。高温胁迫条件下，番茄幼苗类胡萝卜素含量无显著变化，叶绿素含量降低但未达到显著水平。高温胁迫下喷施亚精胺，幼苗叶绿素 a、b 和类胡萝卜素含量显著上升，分别增加了31.80%、30.23% 和32.24% 。番茄幼苗叶片的气体交换参数即净光合速率（Pn）、气孔导度（Gs）、胞间CO2浓度（Ci）和蒸腾速率（Tr）在高温胁迫条件下显著降低，与对照相比分别下降了44.39 %、69.23%，28.34%和58.13%。高温胁迫下喷施Spd显著提高Pn、Gs、Tr和Ci含量，与对照相比分别提高了27.83%、50%、20.23%、51.02%。以上结果说明高温胁迫影响番茄幼苗的光合作用主要是因为打破了光合色素合成与降解的平衡，而亚精胺能通过促进光合色素的合成和调节气孔因素来缓解高温胁迫对其生长的抑制。25682 毕业论文关键词：番茄；高温胁迫；亚精胺；徒长 The Effectof Spermidine Alleviating the High Temperature Stress Injury onTomato Seedlings Abstract:This experiment use the tomato cultivar 'Puhong 968' as experimental material, the cultivation mode is substrate culture,and we set up four treatments: spraying distilled water on the leaves at room temperature, spraying spermidine (Spd) on the leaves at room temperature, spraying distilled water on the leaves at high temperature, spraying Spd at high temperature, study the effects of exogenous spermidine under the high temperature stress on tomato seedlings. The results showed that high temperature stress reduced the dry weight of the overground and the underground parts of tomato seedlings. Under the stress condition, the dry weight of the underground increased significantly compared with the seedlings under high temperature stress, and increased by 5.79% when treated with Spd. And the dry weight of the overground recovered to the level as normal. Under the high temperature stress, the content of carotenoid did not change significantly and the content of chlorophyll a, chlorophyll b declined slightly. The content of chlorophyll a, chlorophyll b and carotenoid increased significantly when treated with Spd under the high temperature stress, and increased by 31.80%, 30.23% and 32.24% respectively. High temperature stress significantly reduced the tomato leaves net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci) and transpiration rate (Tr), declined by 44.39%, 69.23% 28.34% and 58.13% compared with control respectively. Under high temperature stress, spraying Spd significantly increased the content of Pn, Gs, Tr and Ci compared with the control, respectively increased by 27.83%, 50%, 20.23% and 51.02%. These results indicated that high temperature stress affects the photosynthesis of tomato seedlings, mainly because that it broke the balance between photosynthetic pigment synthesis and degradation, and Spermidine could alleviate the inhibition of high temperature stress on the growth of tomato seedlings by promoting the synthesis of photosynthetic pigments and regulating stomatal factors. Key words:Tomato; High temperature stress; Spermidine; Spindling 目 录 摘要 1 关键词 1 Abstract 1 Key words 2 引言 2 1 材料与方法 2 1．1 幼苗培育及处理 2 (责任编辑：qin) |